[InstCombine] Preserve fast math flags when combining PHIs
Summary:
When optimizing PHIs which have inputs floating point binary
operators, we preserve all IR flags except the fast math
flags.
This change removes the logic which tracked some of the IR flags
(no wrap, exact) and replaces it by doing an and on the IR flags of
all inputs to the PHI - which will also handle the fast math
flags.
Reviewers: majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D19370
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267139 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed